Chinese officials have condemned a US ship’s passage near disputed islands in the South China Sea as “illegal” and a threat to their country’s sovereignty.The guided-missile destroyer USS Lassen breached the 12-nautical mile zone China claims around Subi and Mischief reefs in the Spratly archipelago.The US has confirmed the operation took place, apparently as part of its Freedom of Navigation programme.The operation is a challenge to China’s claims over the artificial islands.